Film magazine with sound drum



May 5, 1942. w, E. MERRIMAN FILM MAGAZINE WITH SOUND DRUM Original Filed Oct. 13, 1938 A INVENTOR @WM/3W I Evy@ r /l l A RNEYS .Patented May 54,

2,232,074 FILM MAGAZINE wrm SOUND DRUM William E. Merriman, Rochester, N. Y., assigner to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey Original application October 13, 1938,'Seriai No.

234,809. Divided and this application December 14, 1939, Serial No. 309,212

Claims.

The present invention relates to a sound camera of the film magazine type in which a lm strip is intermittently passed in front of a picture exposing aperture, and is then continuously' passed. in front of a sound exposing aperture which is spaced a definite distance from the picture aperture. This application is a division of' the applicants copending application #234,809, iiled October 13, i938, which has now matured into Patent No. 2,196,736, issued April 9, i940.

in order to secure a true reproduction on the film strip of the sound being recorded, it is highly essential thatthe film strip be moved at a substantially constant and uniform lineal speed past the sound recording aperture, and that the sound drum be spaced the proper distance from the objective lens of the sound optical system.

As is well known, it is diiilcult and highly expensive to manufacture parts which are absolutely free from slight imperfections and/or eccentricities. These imperfections and eccen tricties in the various film driving members together with any slight imperfection in the lm strip itself may cause small momentary variations or fluctuations in the lineal speed of the :lm strip as the latter passes the sound aperture. Such variations, if not corrected. willA obviously distort the sound record, the disadvantages of which are obvious to those in the art. In addition, in order to accurately record the higher vision of a support for the sound drum which will not only support the latter in registry with the sound aperture, but will also maintain the film strip on the sound drum the proper distance from the sound objective lens.

A, further object of the invention is the provision of a rotary stabilizer which automatically adjusts itselie to compensate for minor variations in the feeding mechanism so as'to insure a uniform nlm speed at the point of sound recording.

Yet another object of the invention is the provision of such a stabilizer which can be attached to existing cameras of the sound magazine type.

.A further object of the invention is the provision of a stabilizer which is automatic in its operation and thus requires no attention on the part of the operator.

Still another object of the invention is the provision of a stabilizer of the class described which is inexpensive to manufacture, simple in construction, automatic in its operation, and highly desirable in its results.

Yet another object of the invention is the provision of a film magazine adapted to be removably positioned within a camera, and provided. with a sound drum over which the movfing film strip is guided during the sound recording operation.

Another object of the invention is the pro vision of a film magazine in which a sound drum is mounted and supported substantially in alignment with the sound aperture of the magazine.

To these and other ends, the invention resides in certain improvements and combinations of parts all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the speciiication.

In the drawing:

Fig. 1 is a side view of a sound camera of the illm magazine type with the side plate of the camera and the magazine cover removed, and with a portion of the magazine in section, showing the mechanism for moving the film strip through the magazine, and the relation thereto of a rotary stabilizer constructed in accordance with the preferred embodiment oi the invention.

Fig. 2 is a fragmentary sectional view of a portion of the camera and magazine illustrated in Fig. l, but on a larger scale than thelatter, showing one method of operatively connecting the rotary stabilizer to the sound recording drum for maintaining a uniform. lm speed at the soundaperture; and for retaining the sound drum the proper distance from the objective lens of the sound optical system.

Fig' 3 is a view similar to Fig. 2, showing a modified arrangement for connecting the stabilizer to the sound drum; A

Fig. 4 is a view similar to Figs. 2 and 3 showing a still further modication of connecting or clutching the stabilizer to the sounddrum; and

Fig. 5 is an end view of a portion of the mechanism illustrated in Fig. 3 showing the arrangement by which the opening in the iilm magazine is closed to aiford the necessary ligh't loci: therefor.

Similar reference numerals throughout the' various views indicate the same parts.

Fig. 1 of the drawing shows a sound camera formed with a case or housing II on the front of which the camera orpicture objective lens I2is mounted. A nlm magazine, generally indicated bythe numeral I3, is placeable within the camera housing and contains a supplyof 'nlm which is intermittently fed past a pictureexposing aperture to record the picture, and is then continuously fed past a sound aperture to record the sound image on the marginal edge of the nlm, all as will be hereinafter more fully explained. A dennite length of nlm is maintained between the picture and sound apertures so as to maintain the proper synchronism besuitable and well-known construction and-do not constitute a part of the present invention.

It is well known inthe art, that accurate and true reproduction of the sound can only be securerd when the nlm strip is fed at a constant mentary variations in the various feeding mechanisrrlsl will tend to correspondingly vary the speed of the sound drum 26, and hence the speed of the nlm strip F past the sound aperture 26,

- thus distorting the sound image, the disadvantween the picture taking and the sound recording, as is well known in the art.

The nlm magazine I3 contains a Supply roll I4 of unexposed nlm. The nlm strip F is drawn from the roll I4 by a constantly driven sprocket I6, the teeth I6 of which engage the marginal perforations in the nlm strip to feed the latter -to the upper supplynlm loop I1 and the nlm gate I6. A suitable pull-down mechanism' I9 intermittently pulls or feeds the nlm strip through the gate I8 and past the picture-exposing aperture where the nlm strip is exposedv to the image formed by the picture ob- ,jective lens I2. 'I'he strip F then passes downwardly tothe lower nlm loop 2I formed by a spring 22 of the shape best shown in Fig. l.. This spring is so shaped as to also hold the moving nlm strip against a pair of -rollers 23 positioned below the sprocket I6, as clearly Ashown in Fig. l.

The strip F is then looped over a sound drum il, to be later more muy described, and then under -a guide roller 21 and nnally between the sprocket I6 and the rollers 23 to the takeup roll 26, all as clearly shown in Fig. 1. As the strip tages of which are obvious to those in the art.

In order to overcome these disadvantages, the present invention provides a rotary stabilizer, or viscous flywheel, generally indicated by the numeral 42. This stabilizer is mounted in the mechanism chamber and is operatively connected to and driven by the sound drum 26, in al manner to'be presently described. This stabilizer is arranged to-.automatically and mechanically dampen or nlter out any slight momentary .variations in the speed of the drum 26, thus insuring a smooth and substantially uniform speed of the nlm strip past the sound aperture 29. In addition the supporting vmeans for the stabilizer engages the drum to support the latter substantially in registry with the sound aperture, as well of the stripy passes across a sound aperture 26 for recording the sound image on the nlm strip.

It is apparent from an. inspection of Fig. 1, that as the sprocket I6 is driven the nlm strip F will be drawn over the drum26 to rotate the latter, and to continuously feed the strip F past the sound aperture 26, the drums being arranged in a loop 33 of the strip F.- 'I'he pulldown mechanism I9 on the other hand, intermittently feeds the strip F through the nlm gate I8 and past the picture aperture 20. 'I'he mechanism for driving the sprocket l5 and the pull-down I9 are positioned in a mechanism chamber 30 formed by the spaced walls 6l and.32 on the sides o`i the camera housing II- An vouter wall 46 of the camera housing is spaced from and secured to the wall 32 in any suitable and welllmown manner.

In recording the sound, the image of a lamp nlament 34 passes through a condensing lens 36 and is imaged on a galvanometer mirror 36 which is connected to the sound pickup mechanism, not shown. The image on the galvanometer miras retaining the drum the proper distance from the lens 46. By means of such an arrangement a true, accurate recording of the sound is assured.

The stabilizer 42 is mounted on and supported byfa shaft 43 which is slidable axially in bearings `44 in the chamber 30. This stabilizer, in the present embodiment, is in the form of a viscous ny-wheel and comprises an outer cylindrical member 46 formed with a hub 46a rigidly secured to and movable as a. unit with a shaft 43, and a secondary cylindrical member 41 positioned within the outer member 46 and loosely mounted on a shaft 43, as clearly shown in Fig. 2. The space 48 between the members 46 and 41 is filled with a nuid 46, such as oil, which affords the sole driving connection between the two members 46 and 41. Suitable seals 52 are provided between the shaft 43 and the outer member 46. As the stabilizers 42 in Figs. 2, 3 and 4 are identical in construction the detailed showing thereof is made only in Fig. 2, the remaining ngures merely showing the outside view of the complete sta- -bilizer.

It is apparent from inspection of Fig. 2 that ror 36 is reflected onto a light slit 31 formed in a plate 36. The portion of the sound image which passes through the slit 31 is renected by means of a prism 36 and a sound objective lens 4l through the sound aperture 26 and onto the nlm strip F, all as well known to those in the art'.

The above-described mechanisms, with the exception of the sound drum 26, may be of any guiar speed.

46 will also rotate as a unit therewith. When, however, the member -46 is thus rotated, the inner surfaces 50 thereof will frictionally engage the oil 49 and will provide, in eiect, a slipping friction clutch between the mem-ber 46 and the oil 4l to gradually Ibring the latter, as a unit, up to the speed vof the member 46. The rotating body of oil 49 will, in turn, frictionally engage the outer surface 6I of the inner member 41 to drive the latter. Finally the inner and outer` members will rotate, as a unit, at the saniean- However, should the speed of the shaft 43 momentarily increase, the speed of the outer membery46will correspondingly increase. The inner member 41 and the oil 46, due to their inertia,

will however tend to rotate at the same speed and will thus act as a brake on the outer member 46 to return the latter and the shaft 43 to their previous speeds. If, on the other hand, the shaft 43 tends to momentarily decrease in speed, the outer member 46 will thus tend to run slower than the inner member 46 and the oil 49. These latter members will then act as a driving member and will tend to bring the outer member 46 up to the speed of the inner member t1. Thus the inertia of the rotating member lil and the body of oil 49 will tend to maintain the speed of the outer member 46, and hence the shaft 43, substantially constant and uniform. It is apparent, therefore, that such a stabilizer will effectively dampen or filter out any slight momentary ,variations in the speed of the shaft 43 and thus hold the speed of the latter substantially constant and uniform.

It is also apparent that if the shaft 43 is suitably connected' to and driven from the drum 26., the stabilizer 42 will automatically adjust itself to compensate for any slight momentary variations in the lineal speed of the drum 26 caused by imperfections in the drive members or the film strip, as pointed out above. As the drum l'i6 is thus maintained at a substantially uniform speed, the film strip F will be fed 'past the sound aperture 29 at a uniform rate to provide an accurate recording of the sound image, the advantages of which are obvious to those in the art. vIn addition, the shaft 43 will support the drum 26 and will thus bring the horizontal axis thereof substantially in alignment with the sound aperture 29. But what is more important, the shaft i3 will accurately maintain the film strip F as it passes the aperture 29, the proper distance from the lens irrespective of the position of the Wall 53 of the magazine I3. In the various modifications, the shaft 43 and the stabilizer i2 are permanently mounted in the camera housing, and are automatically coupled or clutched to the sound drum 26 on placing or positioning the magazine I3 within the camera housing.

In the embodiment illustrated in Fig. 2, the left end of the shaft 43 extends through the wall 3l of the mechanism chamber 30 and through registering opening 55 formed in the side 55 of the magazine i3. The shaft is formed with a tapered portion 51 whichis arranged to engage a correspondingly tapered periphery 58 of a centra! opening 59 of the drum 25. This engagement of the portion 51 with the periphery 5B forms, in effect, a friction clutch which affords a driving connection between the drum 2li and the shaft 43, as is apparent from an inspection of this figure.

A ieaf spring 60 has one end @I thereof secured to the wall 32 while a lug or protuberance '62 on thefree end thereof engages the right end 53 of the shaft43 to urge the latter to the left, as viewed in Fig. 2, to maintain the portion 57.4 and the periphery 53 in frictional contact. Thus the drum 26 is held in driving engagement with the shaft 43, and the latter serves. to support the drum so that the horizontal axis thereof will be maintained in registry with the sound aperture' 28 and the film positioned the proper distance from the sound objective-lens 40. A protuberance or lug 54 formed on the cover 65'of the magazine I3 engages theleft face 66 of the drum 26 and cooperates with the shaft 43 to support the drum. In order to prevent fogging of the film strip F, a suitable light lock must necessarily be provided for the opening l.rigidly secured to the shaft 43.

55. In the embodiment shown in Fig. 2, such a light lock ls provided by forming an annular flange or collar A61 around the opening 55. This flange is arranged to extend hito a registering annular recess 68 formed in the drum 26, as

clearly shown in Fig. 2.

By means of this arrangement, the shaft 43 and the stabilizer 42 are operatively connected to and driven by the drum 23. Therefore, any slight momentary variations in the speed of the drum 26, for the reasons pointed out above, will be immediately dampened or filtered ,out by the stabilizer 42 thus insuring a smooth uniform speed of the drum 26. In addition, the fllm strip will be accurately positioned relative to the lens 40. With the speed and position of the film strip thus precisely maintained, the strip will accurately record the sound image which passes through the slit 31. v

When the magazine I3 is not in the camera housing II, the spring '60 slides the shaft 43 leftwardly in the bearings 44, as viewed in Fig. 2, until the hub- 46a engages the left-hand bearing 44 to limit further leftward movement of the shaft 43.V The shaft remains inthis shifted position as long as the housing I I contains no magazine I3. However, when the magazine is placed in the camera housing, the opening 59 of the drum 26 is brought into registry with the shaft 43. The magazine is now slid into position to bring the periphery 53 of the opening 5S into engagement with the tapered portion 51 of the shaft 43. The latter is then slid axially to the right in the bearings 44 until the parts are in the position' shown in Fig. 2, and a fric tion driving engagement is provided between a drum 'Z6 and a shaft 43.

A modified driving connection between the drum 2'6 and the shaft 43 is shown in Fig. 3. Parts in this modification which correspond to those in Fig. 2 are designated by the same numerals and need not be further described. In this modification, the shaft 43 is the saine diameter for its full length and extends into a cylindrical opening 15 formed in the drum I2,6. The opening 15 may be of such a size as to slidably receive the shaft 43 to provide a slight driving connection therewith. It is preferred, however, to provide an additional means in the form of a friction clutch, generally indicated by the numeral 14, for operatively connecting the drum 26 in driving engagement with the shaft 43.

To secure this result, the drum 26 is Aformed with a reduced portion or collar 16 which extends through an opening 11 in the side wall 18 of the magazine I3. The outer end of the collar 16 is formed to provide a radially extending disk 13 which registers with a similar disk 88 One or both of the disks 19 and 80 are provided with a facing 8| of cork or other suitable material to provide a friction clutch drive between the two disks 19 and 83 so that the stabilizer 42 may be operatively connected to the drum 26 to control y the speed of the latter.

In order -to provide suitable space for the friction clutch 14, the wall Si of the vchamber 30 and `the adjacent sides '130i the magazine I3 are lbent out as shown In order to assemble the drum 26 in the magazine I 3, the opening 11 in the side 18 must be slightly larger than the ordm to permit the latter to be passed therethrough and into the magazine, as is apparent' from an inspection of Fig. 3. This large opening is closed, in the present em`- bodimet, by means of a pair of oppositely er ranged U-shaped members 82. of the shape best shown in Fig. 5. These members are slidtowards each other from opposite sides of the collar I9 so that the curved portions I3 ,thereofA A the friction clutch .14 in driving engagement.

A Z-shaped lug fis secured to the surface I6 of the wall 32 and is arranged in the path of the `free end 9| of thespring 94 to limit the rightward movement thereof, as viewed in Fig. 3, when a magazine is placed in the housing, in the man- I ner described in connection with Fig. 2.

The embodiment in Fig. 3, thus affords a friction clutch which operatively connects the stabilizer 42 in driving lengagement with the sound drum 29 so as to nlter out any slight variations in the speed of the drum. The shaft 43 also cooperates with the protuberanoe 94 on the magazine cover Il to support the drum 28 invproper position relative to the sound aperture 29 and the lens 4l.

Fig. 4 shows still another arrangement for forming `a driving connection between the stabilizer 42 and the sound druni. The parts corresponding to those in lthe other figures will be designated by the same numerals. As the sound drum in this embodiment is of a slightly different shape than those described, it will be designated by the numeral 26a. 'Ihis drum is formed with va large central opening 94 in which is press fitted a sleeve or bushing 95. The right hand end of the opening I4 is countersunk to provide an annularrecessarranged to receive the annular flange 91 toprovide alight lock for the opening B in the side Si of 'the magazine, as described in connection with Fig. 2 above.

The right end of the bushing 95 is formed with asista. i

In all of the Vabove arrangements, the sound drum is suitably clutched to the shaft which car- 'ries the stabilizer so that the latter is operatively nlm strip, or imperfections or eccentricities in thus assuring true sound recording, `the advan.

an annular rib or flange 91 the face of which is A formed with a row of axially extending teeth 99 which are arranged to engage with a corre- 'sponding'row of teeth 99 which project axially from a iiange |09 formed on the left end of the shaft 49, Fig. V4. Thus when a magazine` is in position in the camera housing, the teeth 98 and 99 engage to provide a positive driving connection between the stabilizer 42 and its shaft 43 and a sound drum 29a. The left end of the bushi9! which is mounted in the wall I2. as shown.

The drum' 29a is thus resiliently moved toward the shaft 4I to bring the teeth 99 and 99 into engaging relation to positively connect or clutch the drum to the shaft 43 and the stabilizer 42 so that the latter may control the speed of the film strip past the soundaperture, as above described.A As the bushing Il is tightly fitted within the drum 24a it, in effect, is a part thereof so that the teeth 99 may be broadly considered as formed on the sound drum.

the 'various driving members. uniform sound drum speed is insured. In addition, the stabilizer'shaft accurately positions the film strip relative to the sound objective lens,

tages .of which are obvious.

While certain embodiments of the invention have been disclosed, it is to be understood that the inventive idea may be carried out in a number of ways. This application is therefore not to be limited to the precise details described, but is intended to cover, all variations and modifications thereof falling within the spirit of the invention or the scope of the appended claims. I claim: 1. A film magazine comprising a casing provided with a picture taking aperture and a sound recording aperture, `a film strip in said magazine extending from a supply film roll to a take-up roll and past said picture yand sound apertures,

film guidingmeans for supporting the film ad-f jacent said picture aperture, and an idler sound lrecording drum loosely mounted in said casing opposite the sound aperture for supporting the film opposite said sound aperture and adapted to be rotated solely by the movement of the illm strip thereover.

2.*A illm magazine comprising a casing provided with a picture taking aperture and a sound recording aperture, a nini strip in said magazine extending from a supply nlm roll to a take-up roll and past said picture and' sound apertures, rotatable nlm guiding means loosely mounted in said casing opposite said sound aperture forsupporting the iilm in alignment with said sound aperture and adapted to be vrotated solely by the movement of the film strip thereover, provided with a spindle receiving portion positioned entirely within said casingand available from the exterior thereof, and for supporting the film opposite said sound aperture.

3. Al film magazine comprising a 'casing provided with apicture taking aperture and a sound recording aperture, a nlm strip in said magazine extending from a supply film roll to a take-up roll and past said picture and sound apertures, film guiding means for supporting the illm adjacent said picture aperture, a sound recording drum positioned in said casing in alignment with said sound aperture for supporting said film opposite said sound aperture and adapted to be rotated solely by the movement of the film strip' positioned entirely within said drum but available Thus a smooth sesame from the exterior thereof, a light lock on said easing adjacent said portion.. and means entirely within casing for loosely but rotatably supporting said drum. l

5. A film magazine comprising a casing formed i with sides and a' coser and provided with a pieture taking aperture and a sound recording oper iure in certain of said sides, a film strip in said magazine extending trom a supply nlm roll to a take-up roll and past said picture and sound apertures, filmA guide means on one of said sides Kor simportine` the nlm adjacent said picture aperture, a sound drum positioned at one end of said casing iorksupporting said fllrn opposite said sound aperture, said drum being provided with a spindle receiving portion positioned within said casing but available from the exterior therei of through another side thereof and heine formed with-an annular recess adjacent said portion, a danze onsaid other side extending into said recess to provide a light lock for said casing adjacent said portion, and means on said cover cooperating with said Hnge for supporting said drum substantially in alignment with said sound aperture.

WILLIAM E. MERRIMAN. 

